Prevalence and extent of atherosclerotic coronary artery disease and related outcome based on coronary computed tomographic angiography in asymptomatic elderly patients: retrospective cohort study

Long-term prognostic utility of computed tomography coronary angiography in older populations

Aims

The long-term prognostic value of coronary computed tomography angiography (CCTA)-identified coronary artery disease (CAD) has not been evaluated in elderly patients (≥70 years). We compared the ability of coronary CCTA to predict 5-year mortality in older vs. younger populations.

Methods and results

From the prospective CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter) registry, we analysed CCTA results according to age <70 years (n = 7198) vs. ≥70 years (n = 1786). The severity of CAD was classified according to: (i) maximal stenosis degree per vessel: none, non-obstructive (1–49%), or obstructive (>50%); (ii) segment involvement score (SIS): number of segments with plaque. Cox-proportional hazard models assessed the relationship between CCTA findings and time to mortality. At a mean 5.6 ± 1.1 year follow-up, CCTA-identified CAD predicted increased mortality compared with patients with a normal CCTA in both <70 years [non-obstructive hazard ratio (HR) confidence interval (CI): 1.70 (1.19–2.41); one-vessel: 1.65 (1.03–2.67); two-vessel: 2.24 (1.21–4.15); three-vessel/left main: 4.12 (2.27–7.46), P < 0.001] and ≥70 years [non-obstructive: 1.84 (1.15–2.95); one-vessel: HR (CI): 2.28 (1.37–3.81); two-vessel: 2.36 (1.33–4.19); three-vessel/left main: 2.41 (1.33–4.36), P = 0.014]. Similarly, SIS was predictive of mortality in both <70 years [SIS 1–3: 1.57 (1.10–2.24); SIS ≥4: 2.42 (1.65–3.57), P < 0.001] and ≥70 years [SIS 1–3: 1.73 (1.07–2.79); SIS ≥4: 2.45 (1.52–3.93), P < 0.001]. CCTA findings similarly predicted long-term major adverse cardiovascular outcomes (MACE) (all-cause mortality, myocardial infarction, and late revascularization) in both groups compared with patients with no CAD.

Conclusion

The presence and extent of CAD is a meaningful stratifier of long-term mortality and MACE in patients aged <70 years and ≥70 years old. The presence of obstructive and non-obstructive disease and the burden of atherosclerosis determined by SIS remain important predictors of prognosis in older populations.

Incremental prognostic value of coronary computed tomography angiography over coronary calcium scoring for major adverse cardiac events in elderly asymptomatic individuals

Aims

Coronary computed tomography angiography (CCTA) and coronary artery calcium score (CACS) have prognostic value for coronary artery disease (CAD) events beyond traditional risk assessment. Age is a risk factor with very high weight and little is known regarding the incremental value of CCTA over CAC for predicting cardiac events in older adults.

Methods and results

Of 27 125 individuals undergoing CCTA, a total of 3145 asymptomatic adults were identified. This study sample was categorized according to tertiles of age (cut-off points: 52 and 62 years). CAD severity was classified as 0, 1–49, and ≥50% maximal stenosis in CCTA, and further categorized according to number of vessels ≥50% stenosis. The Framingham 10-year risk score (FRS) and CACS were employed as major covariates. Major adverse cardiovascular events (MACE) were defined as a composite of all-cause death or non-fatal MI. During a median follow-up of 26 months (interquartile range: 18–41 months), 59 (1.9%) MACE occurred. For patients in the top age tertile, CCTA improved discrimination beyond a model included FRS and CACS (C-statistic: 0.75 vs. 0.70, P-value = 0.015). Likewise, the addition of CCTA improved category-free net reclassification (cNRI) of MACE in patients within the highest age tertile (e.g. cNRI = 0.75; proportion of events/non-events reclassified were 50 and 25%, respectively; P-value <0.05, all). CCTA displayed no incremental benefit beyond FRS and CACS for prediction of MACE in the lower age tertiles.

Conclusion

CCTA provides added prognostic value beyond cardiac risk factors and CACS for the prediction of MACE in asymptomatic older adults.

Prognostic value of segment involvement score compared to other measures of coronary atherosclerosis by computed tomography: A systematic review and meta-analysis

BACKGROUND

The segment involvement score (SIS) is a semiquantitative measure of the extent of atherosclerosis burden by coronary computed tomography angiography (CTA). We sought to evaluate by meta-analysis the prognostic value of SIS, and to compare it with other CTA measures of coronary artery disease (CAD).

METHODS

Electronic databases from 1946 to January 2016 were searched. Studies reporting SIS, or an equivalent measure by coronary CTA, and clinical outcomes were included. Maximally adjusted hazard ratios (HR), predominantly for clinical variables, were extracted for SIS, obstructive CAD, Agatston coronary artery calcium score, and plaque composition. These were pooled using DerSimonian-Laird random effects models.

RESULTS

Eleven nonrandomized studies with good methodological quality enrolling 9777 subjects (mean age 61 ± 11 years, 57% male, mean follow up 3.3 years) who had 472 (4.8%) MACE (cardiac or all cause death, non-fatal myocardial infarction or late revascularization), were included. SIS (per segment increase) had pooled HR of 1.25 (95% CI: 1.16,1.35; I² = 71.4%, p < 0.001) for MACE. HR for MACE was 1.37 (95% CI: 1.32,1.42; I² = 95.6%, p < 0.001) for number of segments with stenosis (per segment increase), 3.39 (95% CI: 1.65,6.99; I² = 87.8%, p = 0.001) for obstructive CAD (binary variable) and 1.00 (95% CI: 1.00,1.01; I² = 75.0%, p = 0.490) for Agatston score (per unit increase). HRs by plaque composition (calcified, non-calcified and mixed; per segment change) were 1.24 (95% CI: 1.10,1.39; I² = 81.6%, p = 0.001), 1.20 (95% CI: 0.97,1.48; I² = 92.9%, p = 0.093) and 1.27 (95% CI: 1.03,1.58; I² = 89.8%, p = 0.029), respectively.

CONCLUSION

Despite heterogeneity in endpoints, extent of CAD as quantified by SIS on coronary CTA is a strong, independent predictor of cardiovascular events.

Age-related differences in image quality of prospectively ECG-triggered axial and helical scans for coronary CT angiography

We investigated the underlying reasons for the occurrence of misalignment artifacts in prospectively ECG-triggered axial coronary CT angiography scans. In this study we analyzed 56 consecutive patients scanned in axial mode and 66 consecutive patients scanned in helical mode. Predictors for the occurrence of misalignment artifacts were evaluated by multivariable logistic regression analysis for those patients scanned in the axial mode; advanced age was identified as the sole independent predictor (odds ratio: 1.088; 95 % CI: 1.012-1.170; p = 0.0228). In a comparison with the patients scanned in the helical mode, the image quality score for patients aged 65 years or older was significantly higher in helical mode than in axial mode (2.6 ± 0.5 and 2.4 ± 0.7, respectively; p = 0.0313). Misalignment artifacts in the image are more common in the elderly than in younger. Helical mode should be preferred in this older patient population to allow for good diagnostic image quality.

Inter-Arm Blood Pressure Difference in Hospitalized Elderly Patients Is Not Associated With Excess Mortality

Inter-arm blood pressure difference (IAD) has been found to be associated with cardiovascular mortality. Its clinical significance and association with mortality in the elderly is not well defined. This study evaluated the association of IAD with mortality in a cohort of hospitalized elderly individuals. Blood pressure (BP) was measured simultaneously in both arms in elderly individuals (older than 65 years) hospitalized in a geriatric ward from October 2012 to July 2014. During the study period, 445 patients, mostly women (54.8%) with a mean age of 85±5 years, were recruited. Systolic and diastolic IAD were >10 mm Hg in 102 (22.9%) and 76 (17.1%) patients, respectively. Patients were followed for an average of 342±201 days. During follow-up, 102 patients (22.9%) died. Mortality was not associated with systolic or diastolic IAD. It is therefore questionable whether BP should be routinely measured in both arms in the elderly.

Hepatic fibrosis assessed using transient elastography independently associated with coronary artery calcification

BACKGROUND AND AIM

Non-alcoholic fatty liver disease (NAFLD) has a close relationship with coronary atherosclerosis. We investigated the association between coronary atherosclerosis and liver fibrosis, represented as coronary artery calcification (CAC) score, and live stiffness (LS) value assessed using transient elastography (TE), respectively, in patients with NAFLD.

METHODS

Between January 2013 and March 2014, a total of 285 asymptomatic subjects without chronic liver and ischemic heart diseases who underwent comprehensive medical health check-up were recruited. NAFLD was defined as controlled attenuation parameter (CAP) ≥ 250 dB/m on TE.

RESULTS

The median age of the study population (men 161 and women 124) was 56 (interquartile [IQR], 50-63) years. Of these, 142 (49.8%) subjects had NAFLD. Among subjects with NAFLD, CAC score was independently correlated with the male gender (β = 0.230; P = 0.010), elevated erythrocyte sedimentation rate (β = 0.220; P = 0.019), reduced estimated glomerular filtration rate (β=-0.220; P = 0.004), increased left ventricular mass index (β = 0.226; P = 0.027), and higher LS values (β = 0.274; P < 0.001). In addition, alanine aminotransferase level (β = 0.214, P = 0.012) and CAC score (β = 0.311; P = 0.001) are the only independent factors associated with LS values in subjects with NAFLD.

CONCLUSIONS

Higher CAC score was independently correlated with LS values in subjects with NAFLD. However, it should be further investigated whether TE can be incorporated into a screening tool to identify the high-risk population for coronary artery disease.